For all those who need information about real-world XML Schema usage,
the following paper may be valuable.
Regards,
Ralf Laemmel
Analysis of XML schema usage: XML schema analysis aims to extract
quantitative and qualitative information from actual XML schemas. To
this end, XML schemas are measured through systematic algorithms, on the
basis of the intrinsic feature model of the XSD language. XML schema
analysis is a derivative of software analysis (program analysis) and of
software code metrics, in particular. The present article introduces
essential concepts of XML schema analysis and applies them to the
important problem of understanding XML schema usage in practice.
Analyses for feature counts, idiosyncrasy counts, size metrics,
complexity metrics, and XML schema styles are executed on a large corpus
of real-world XML schemas.
http://www.cwi.nl/~ralf/xml05/http://www.idealliance.org/proceedings/xml05/abstracts/paper49.HTML